Page 149 - Casting of Angels- Dave Parvin

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Dave Parvin is best
known for his realistic
figurative sculptures Making a Mold
form miniatures to
monumental in bronze,
pewter, acrylic, and
Forton MG. In Using Alginate
addition, he is one of
only 5 sculptors to have
been designated as a
Certified Lft casting Why Alginate?
Instructor by the
Association of By David E. Parvin, A.L.I.
lifecasters international. He routinely offers
workshops in lifecastinq mold making, art About 20 years ago, life-casters on the cutting edge began experimenting
marketing, and realistic sculpting. He may be with alginate for directly molding the human form. Up until that time, most had
reached at parvinstudio@comcast.net but used plaster. Plaster has at least two disadvantages. Esthetically, its ability of
prefers talking to typing at 303-321-1074. capturing detail is minimal. But more importantly, applied directly to skin,
plaster can be hazardous to the subject's health. Alginate, whose principal
ingredient alginic acid is extracted from seaweed, has long been used by dentists

to make impressions of teeth (see the following article for more information on
the history of alginate). Able to capture the finest detail while being harmless to
both the castor and the castee, alginate has become the standard mold material
Compared to other flexible mold for life casting. But taxidermists may find alginate a very useful substance for
materials such as the various mold making as well.
Compared to other flexible mold materials such as the various types of
types of rubber compounds, rubber compounds, alginate has definite advantages. One is cost. For example,
most quality silicone rubbers cost around $10 per pound. But a pound o£
alginate has definite advantages.
alginate mixed with water is 1/3 to 1/4 that. Secondly, alginate is completely
One is cost. nontoxic to skin contact and has no harmful fumes; it's even odorless. It's also a
cinch to mix. While silicone rubbers are not temperamental, most urethanes are.
Critical' care must be taken in measuring and in thoroughly mixing to prevent
soft spots that never cure. Certainly there are optimum alginate/water ratios for

particular applications, but it mixes easily and as long as it's wet, it will set-up.
Because it's water soluble, clean up is a piece of cake. Alginate doesn't stick to
anything though it will tangle in hair, feathers, fuzzy cloth, etc. unless coated
with a release (more about this later). Perhaps its greatest advantage is that its
setting time varies from as little as a minute to 8 or 9 minutes allowing for
something to be very quickly molded. O.K., so what's the bad news? The only
negative is that it's fragile and generally an alginate mold can only be used once
or at best only a few times and will quickly dry out and cannot be stored for
future use.

MAKING A MOLD
Anyone who has ever made a rubber mold will have no difficulty in making
an alginate mold. But even someone who have never made a mold should have
no difficulty if he/she simply follows the steps below: Make sure that you have
everything that you will need such as some alginate. Alginates differ in consis-
tencies, setting times, strength, etc. depending on the brand. My personal
Assemble everythingyou will need before starting favorites are Moldgel Regular Set and Slow Set made by Artmolds, Inc. (I
explain why later in this article). The amount needed is dependent, of course, on
the project. the size of the mold, but a couple of pounds will be sufficient for most small
molds. Next you will need something for an outer or "mother" mold such as a

Tupperware container or a milk carton. A scale accurate to a half-ounce or so
and several small plastic containers will suffice for measuring and mixing. Some
sort of a mixer such as one used for paint and attached to an electric drill; or

even a whisk will do for small batches using up to a couple of pounds of water.
Parts of thin plastic pill trays, while not essential, will make two halves of a
mold fit together more precisely. Any number of things could be used for the
final casting of the positive such as plaster, hydrocal, urethane resin, etc. The
last and most important thing needed is something to cast. For this article we'll
use a fish.
I estimated how much mixed alginate it would take to fill the plastic food